Foaming compositions



United States l atent O 3,311,574 FOAMING CONEOSITIONS William David Samuel Bowering, St. Lambert, and Neil Bonnette Graham, St. Hilaire, Quebec, Canada, assignors to Canadian Industries Limited, Montreal, Quebec, Canada, a corporation of Canada No Drawing. Filed Apr. 23, 1963, Ser. No. 274,950 Claims priority, application Great Britain, Apr. 25, 1962, 15,812/ 62 15 Claims. (Cl. 260--2.5)

This invention relates to novel compositions suitable for the production of foamed cellular polymeric materials, novel foaming processes employing such compositions and the novel foamed cellular polymeric materials obtained therefrom.

It is known to manufacture solid foamed polymeric materials by expanding polymeric materials with numerous gas bubbles to yield products having densities as low as one or two pounds per cubic foot. Such polymeric foams are known in both rigid and flexible forms, and typical examples thereof are the polyurethane and polystyrene foams. The former are capable of being foamedin-place to fill cavities of irregular shape, and they may also be dispensed from mixing machines to coat articles with thick insulating blankets. Their isocyanate ingredients are, however, undesirably toxic under some conditions. The polystyrene foams, on the other hand, are not conveniently foamed-in'place since requiring external heating for this purpose and, in addition, they do not flow easily into complex cavities and do not bond to surfaces. It is an object of this invention to provide new foaming compositions which are suitable for the production of foamed-in-place polymeric materials and the ingredients of which do not present the toxicity problems encountered with the ingredients of polyurethane foaming compositions. Another object of the invention is to provide new compositions which yield polymeric foams having a wide variety of properties suitable for many end uses. Additional objects of the invention will appear hereinafter.

The new foaming compositions of this invention comprise at least one polymerizable vinyl ether containing at least two vinyl groups per molecule, a foaming agent, an acidic catalyst and, optionally, at least one compound reactive with said vinyl ether.

Any foaming agent may be used in the compositions, particularly those which have been proposed for use in conjunction with polyurethane materials for the production of foamed or cellular materials. Volatile foaming agents are particularly suitable.

As suitable acidic catalysts, there may be used, in partic ular, those acidic catalysts which have been proposed for the polymerization of vinyl ethers and, more particularly, those which have been proposed for the polymerization of vinyl ethers containing two vinyl groups. Especially useful catalysts are the strong acidic ones.

The compounds reactive with the polymerizable vinyl ethers may be any such compounds. Those which have been found particularly suitable for incorporation in the foaming compositions of this invention are compounds which are reactive with the vinyl ethers under cationic catalysis conditions, e.g. 2-pheny1-3,4-dihydro-2H-pyran and 2-alkyl-3,4-dihydro-2H-pyran. Such compounds tend to slow down the rate of gelation of the compositions and thus yield slower hardening foams.

Of the aforesaid particularly suitable compounds reactive with the polymerizable vinyl ethers, those which have been found to be especially useful are amido compounds containing at least two amido groups per molecule, carbamate compounds containing at least two carbamate groups per molecule and polymerizable alpha, beta-monoethylenically unsaturated compounds, the latter being used p- 3,311,574 Patented Mar. 28, 1967 tionally in admixture with phenolic compounds, aliphatic monohydric or polyhydric alcohols and epoxidized materials containing at least one epoxide group per molecule.

Thus, in the especially useful foaming compositions of this invention, at least one polymerizable vinyl ether containing at least two vinyl groups per molecule is admixed with the following reactive materials, preferably in the proportions indicated:

(a) A compatible amido compound containing at least two amido groups per molecule, the proportions of the ingredients being preferably such that the number of amido groups provided by said amido compound is less than 10% of the number of vinyl groups provided by said vinyl ether;

(b) A compatible carbamate compound containing at least two carbamate groups per molecule, the proportions of the ingredients being preferably such that the number of carbamate groups provided by said carbamate compound is less than of the number of vinyl groups provided by said vinyl ether;

(0) A compatible polymerizable alpha, beta-monoethylenically unsaturated compound, the proportions of the ingredients being preferably such that the number of ethylenically unsaturated groups provided by said ethylenically unsaturated compound is not greater than three times the 'number of vinyl groups provided by said vinyl ether;

(d) A compatible polymerizable alpha, beta-monoethylenically unsaturated compound, and a compatible phenolic compound, the proportions of the ingredients being preferably such that the combined number of ethylenically unsaturated and hydroxyl groups provided by said unsaturated compound and phenolic compound, respectively, ranges from less than 75 of the number of vinyl groups provided by said vinyl ether when the compositions contain a large amount of phenolic compound but a small amount of ethylenically unsaturated compound, to not more than three times the number of vinyl groups provided by said Vinyl other when the compositions contain a large amount of ethylenically unsaturated compound but a small amount of phenolic compound;

(e) A compatible 'alpha, beta-monoethylenically unsaturated compound and a compatible aliphatic monohydric or polyhydric alcohol, the proportions of the ingredients being preferably such that the combined number of ethylenically unsaturated and hydroxyl groups provided by said ethylenically unsaturated compound and alcohol, respectively, ranges from less than 75 of the number of vinyl groups provided by said vinyl ether when the compositions contain a large amount of alcohol but a small amount of ethylenically unsaturated compound, to not more than three times the number of vinyl groups provided by said vinyl ether when the compositions contain a large amount of ethylenically unsaturated compound but a small amount of alcohol; or

(f) A compatible alpha, beta-monoethylenically unsaturated compound and a compatible epoxidized ma-.

terial containing at least one epoxide group per molecule, the proportions of the ingredient being preferably such that the number of ethylenically unsaturated groups provided by said ethylenically unsaturated compound is not more than three times the combined number of vinyl groups and epoxide groups provided by said vinyl ether and epoxidized material, respectively.

When the compositions of this invention contain only the vinyl ether, foaming agent and catalyst as essential ingredients, the polymerization of the vinyl ether under the influence of the catalyst and in the presence of the foaming agent leads to the formation of solid polymeric foamed materials.

When the compositions also contain at least one vinyl ether-reactive compound, the said compound or compounds undergo chemical reaction with the vinyl ether under the influence of the catalyst, leading to the formation ofp-olymeric foamed materials of widely varied properties and utilities.

It has been found that organic bases such as the dimethyl tertiary amines derived from coconut fatty acids can be used to retard the reaction of the foam-forming ingredients of the compositions.

The foaming compositions of this invention may also include materials, copolymerizable with the other ingredients thereof, e.g. cyclic anhydrides, as well as non-reactive additives which may be flame retardants, surfactants, dyes, fillers, stabilizers, antioxidants, extenders, plasticizers and viscosity-modifiers such as polyvinyl chloride, vinyl acetate/ vinyl chloride copolymers and rubbers.

The polymerizable vinyl ethers, suitable for use in the foaming compositions of this invention, are ethers in which at least two vinyl groups are each joined to an ether oxygen atom.

They may have a generic formula such as wherein n is an integer having a value of at least 2, R and R are members selected from the group consisting of hydrogen and alkyl radicals, R is a member selected from the group consisting of hydrogen, halogen atoms and hydrocarbyl radicals, R and R taken together form a member selected from the group consisting of two hydrogen atoms, two alkyl radicals and one alkylene or substituted alkylene radical, R is a member selected from the group consisting of hydrogen and alkyl radicals, and A is a linking group having a valence equal to 12.

Examples of the aforementioned vinyl ethers are:

divinyl ether, di-isopropenyl ether, butanediol divinyl ether, propylene oxide/polyol condensates of the formulae after, 1,2 ethanedioxy bis-(3',4'-dihydro-2H-pyran-2'- carbonyl) of the formula bis-(3,4-dihydro-2H-pyran-2-methyl) succinate of the formula 1,2-bis(3',4'-dihydro-2'H pyran 2' oxy)ethane of the formula 1,1 bis(3,4' dihydro Z'H-pyran 2' methoxy)ethane of the formula 1,2 et hanedioxy bis(3',4' dihydro 5 methyl 2'H- pyran-2'-carbonyl) of the formula 1,2 bis(3,4' dihydro -5 methyl Z'H pyran 2'- oxy)ethane of the formula 1,1 bis(3,4' dihydro 5' methyl 2'H pyran 2'- methoxy)et'hane of the formula C H: C H: HaC-C CH: H H2? G-CI-IK H C CH-CHzO- C-OH2CH C CH l O C 0 toluene 2,4 (bis 3',4' dihydro ZH pyran 2'- methyl) carbamate of the formula HgN-fi-(CHflu-(fi-NH:

and the polyamide derived fromisophthalic acid and pentamethylene diamine.

Examples of polycarbamates are those derived from organic polyisocyanates and polyols such as the condensation product of tolylene diisocyanate and pentamethylene glycol of formula (llHa and the condensation product of diphenylmethane 4,4- diisocyanate and polypropylene glycol of molecular weight 425.

Examples of polymerizable alpha,bet'a-monoethylenically unsaturated compound are 3,4-dihydro-2H-pyran, 2-ethoxy-3,4-dihydro-2H-pyran, 2-alkyl-3,4-dihydro 2H- pyran, -2-pl1enyl-3,4-dihydro-2H-pyran, l-decene, vinyl stearate, lauryl vinyl ether, dibutyl maleate, maleic anhydride, vinyl cyclohexene, alkyl acrylates, alkyl methacrylates, styrene, etc. These compounds preferably should not boil during the foam-forming reaction.

The phenolic compounds and as ingredients in the foaming compositions are those aromatic compounds which contain one or more hydroxyl groups in their molecules such as phenol, alkyl-substituted phenols, e.g. cresols, halogen-substituted phenols, e.g. 2,4,5-trichlorophenol, resorcinolphloroglucinol, catechol, hydroquinone, 2:2-di-p-hydroxyphenylpropane, low molecular weight phenol-terminated polycarbonates, the condensation products of phenols with aldehydes and ketones, etc.

The aliphatic monohydric or polyhydric alcohol ingredients of the foaming compositions of this invention include amyl alcohol, Z-ethylhexyl alcohol, nonyl alcohol, n'decyl alcohol, polypropylene glycol, caster oil, sugar alcohols, alkyl and acyl cellulose derivatives, polyether condensates of polyhydric alcohols and olefin oxides such as the polypropylene oxide condensates of hexahydroxy sugar alcohols and propylene oxide, ethylene glycol, 1,5-pentanediol, glycerol, 1,2,6-hexanetriol and hydroxyl-containing esters and polyesters obtained by condensation of polyhydric alcohols and polybasic acids. The proportions of condensating ingredients in said hydroxyl-containing esters and polyesters may range from one mole of polyol for each carboxylic acid group in the acid to one mole of polycarboxylic acid for each hydroxyl group in the polyol. The first limit gives an ester containing free alcoholic hydroxyl groups whereas the second gives an ester containing carboxylic acid groups; in between these limits, polyesters are formed which contain both hydroxyl and carboxylic acid groups.

By epoxidized materials containing at least one epoxide group per molecule are meant compounds containing at least one group of the formula per molecule. Examples of such compounds are epichlorohydrin, styrene oxide, dia'llyl ether monoxide, cyclohexene oxide, glycidyl phenyl ether, glycidyl stearate, dipeutene dioxide, vinyl cyclohexene dioxide, polyallyl glycidyl ether, diphenylolpropane diglycidyl ether, epoxidized polbutadiene, epoxidized styrene-butadiene copolymers, the resinous condensates of epichlorohydrin and aliphatic or aromatic polyols such as glycerol or 2:2-dip-hydroxyphenyl propane, etc.

Volatile foaming agents suitable for use in the foaming compositions of the invention are those which are soluble or dispersible in the other ingredients of the foaming compositions and are sufficiently volatile that they vaporize during the formation of the foamed polymeric materials. The heat of the catalyzed polymerization reaction causes the foaming agent to boil, and the vapour forms bubbles which expand during the polymerization reaction to give a low density, foamed polymerized mass. Preferred foaming agents are the halogenated hydrocarbons such as trichloromonofiuoromethane, dichlorotetrafiuoroethane, trichlorotrifluoroethane, dibromodifluorourethane, dichlorohexafluorocy- (3H2 -nn o(onmon n O clobutane, methylene chloride, chloroform, trichloroethylene,'carbon tetrachloride and perchloroethylene.

The strong acid catalysts suitable for promoting the reaction of the polymer-forming ingredients of the foaming compositions include the strong protonxlonating acids, such as p-toluenesulphonic acid, and the Lewis acids such as trimethoxyboroxine and boron trifiuoride conveniently employed as the etherate, BF -(C H O. Compositions containing very reactive vinyl ethers such as butanediol divinyl ether can be catalyzed by p-toluenesulphonic acid but a Lewis acid catalyst is preferred for those compositions containing 3,4dihydro-2H-pyranyl compounds including the 3,4-dihydro-2H-pyran-2-methyl- (3,4-dihydro-2H-pyran-2-carboxylate) referred to hereinafter.

It is possible to control the polymerization reaction by employing catalyst combinations e.g. p-toluene sulphonic acid and boron trifluoride or boron trifluoride and trimethoxyboroxine. Other materials which are suitable as catalytic ingredients are ferric chloride, stannic chloride, phosphorus pentachloride, phosphoric acid, perchloric acid, acetic acid, trifluoroacetic acid, trichloroacetic acid, fluoroooric acid, boron trifluoride dihydrate, hydrogen fluoride, antimony pentafluoride, hexafluorophosphoric acid, lead fluoborate, antimony fluoborate, sulphuric acid and silicotungstic acid. The solvent in which the catalyst is dissolved also affects the catalyst reactivity, polypropylene glycol solutions of BF -(C H O being less reactive than xylene solutions of said catalyst. Suitable catalytic amounts range from 0.005% to 2.0% by weight of the compositions, but these amounts are not limitative since the amount of catalyst should be adjusted to the temperature of operation and the foam induction period required. When Lewis acids are used as catalysts in foaming compositions devoid of phenolic or alcoholic ingredients, it is often advantageous to incorporate into the compositions small amounts of cocatalysts such as water, alcohols or carboxylic acids.

Suitable flame-retardants for incorporation in the foaming compositions include trichloroethylphosphate, 2:2-bis(3',5-dibromo-4'-hydroxphenyl) propane, chlorendic acid and polyvinyl chloride, with or Without antimony oxide.

The preferred surfactants are those of the silicone type, examples of which are disclosed in Belgian Patent Nos. 582,362 and 584,089, i.e. being of the siloxane oxyalkylene copolymer type.

In the above list of vinyl ether-reactive materials, preferred proportions are indicated. However, the proportions of such reactive materials in relation to proportions of vinyl ethers may vary considerably. The use of widely differing proportions leads to the formation of foamed materials of differing properties, e.g. different compression strength, density and texture. In order to obtain foamed materials of advantageous properties and of particular utility, it is often necessary to vary the proportions of vinyl ether and vinyl ether-reactive material according to the nature of the reactive material used.

Referring, then, to particularly preferred proportions of the ingredients of the foaming compositions of this invention, it has been found that in the case of compositions containing only a polymerizable vinyl ether as foamable polymer-forming component, preferred proportions are from 50% to by weight of said vinyl ether and from 2% to 30% by weight of volatile foaming agent, the remaining ingredients such as surfactant and flameretardant being present in amounts less than about 15% by weight.

Preferred compositions containing ether-reactive material (a) comprise at least 50% by weight of the vinyl ether, the amount of the amido compound containing at least two amide groups per molecule being such that the number of amido groups provided thereby is less than of the number of vinyl groups provided by said vinyl ether, and from 2% to 30% by weight of the foaming agent, the remaining ingredients such as surfactant and flame-retardant being present in amounts less than about by weight.

The admixture of amido compounds containing at least two amido groups per molecule with the vinyl ethers as ingredients of the foaming compositions slows down the foaming reaction and thus increases the foam induction period with improvement in handling of the foaming process.

In the case of compositions containing ether-reactive material (b) suitable compositions comprise at least 50% by weight of the vinyl ether, the amount of the carbamate compound being such that the number of carbamate groups provided thereby is less than 75% of the number of vinyl groups provided by the vinyl ether, and from 2% to 30% by weight of the foaming agent, the remaining ingredients such as surfactant and flame-retardant being present in amounts less than about 15% by weight.

The inclusion of the carbamate compounds in the compositions results in foams which are tougher and more resilient than foams derived from vinyl ethers alone, and which possess good dimensional stability under conditions of high temperature and humidity.

Preferred compositions having ether-reactive material (0) comprise at least 30% by weight of the vinyl ether, the monoethylenically unsaturated compound in a proportion such that the number of ethylenically unsaturated groups provided thereby is not greater than three times the number of vinyl groups provided by said vinyl ether, and from 2% to 30% by weight of the foaming agent, the remaining ingredients such as surfactant and flame.- retardant being present in amounts less than about 15 by weight.

The inclusion of monoethylenically unsaturated compounds in the foaming compositions imparts a slower rate of set and greater control of rise to the resulting foams than when the compositions only contain the vinyl ethers as polymeriza-ble ingredients.

Compositions containing ether-reactive material (d) preferably comprise at least 30% by weight of the vinyl ether, the proportions of the monoethylenically unsaturated and phenolic compounds being such that the com- 'bined number of ethylenically unsaturated and hydroxyl groups provided thereby ranges from less than 75% of the number of vinyl groups provided by said vinyl ether when the compositions contain a large amount of phenolic compound but a small amount of ethylenically unsaturated compound, to not more than three times the number of vinyl groups provided by said vinyl ether when the composition contains a large amount of ethylenically unsaturated compound but a small amount of phenolic compound, and from 2% to 30% by weight of the foaming agent, the remaining ingredients such as surfactant and flame-retardant being present in amounts less than about 15 by Weight.

The inclusion of the phenolic compound with the monoethylenically unsaturated compounds in the compositions imparts a slower rate of foam set and greater control of foam rise, thus giving better skins and improved colour to the foams.

For compositions containing ether-reactive material (e) preferred proportions are at least 30% by weight of the vinyl ether, the amounts of the monoethylenically unsaturated compound and the aliphatic monohydric or polyhydric alcohol being such that the combined number of ethylenically unsaturated groups and hydroxyl groups providedthereby ranges from less than 75 of the number of vinyl groups provided by said vinyl ether when the compositions contain a large amount of alcohol but a small amount of ethylenically unsaturated compound, to not more than three times the number of vinyl groups provided by said vinyl ether when the compositions contain a large amount of ethylenically unsaturated compound but a small amount of alcohol, and from 2% to 30% by weight of the foaming agent, the remaining ingredients such as surfactant and flame-retardant being present in amounts less than about 15% by weight.

The admixture of the alcohol with the vinyl ether and ethylenically unsaturated ingredients of the compositions gives improved foams characterized by low density and fine even texture.

Preferred compositions containing ether-reactive material (f) comprise at least 30% by weight of the vinyl ether, the monoethylenically unsaturated compound and the epoxidized material being present in amounts such that the number of ethylenically unsaturated groups provided by said compound is not more than three times the combined number of vinyl groups and epoxide groups provided by said vinyl ether, and epoxidized material, respectively, and from 2% to 30% by weight of the foaming agent, the remaining ingredients such as surfactant and flame-retardant being present in amounts less than about 15 by weight.

The presence of epoxidized material in the compositions, in addition to the vinyl ether and monoethylenically unsaturated ingredients, results in improved foams characterized by good tough skins, light colour and fine cell structure.

The ingredients of the foaming compositions may simply be mixed by stirring in a vessel and then quickly poured into a mould. They may also be mixed in the space which is to be filled with foam if it is suitably shaped. When such stirred mixing is used, it is highly desirable that a surfactant be added to the compositions in order to give foams of small bubbles. However, a surfactant is not always essential. For example, in certain foam-dispensing machines, the ingredients are mixed under pressure using a foaming agent which is gaseous at the mixing temperature, the pressure being controllably released, and the frothed mixture is then dispersed to the point of use. In such a frothing machine, a surfactant is not essential. However, in ordinary dispensing machines wherein the foaming compositions are dispensed before foaming starts, the use of a surfactant is often desirable. In many recipes, it has been found that reduction of the amount of surfactant to the point where the bubbles just burst as polymerization is complete gives foams of the known open cell structure.

The foams of this invention in the flexible form may be used for upholstery, mattresses, etc. In the rigid form they are eminently suited for heat and sound insulating purposes, either in closed cavities or as enveloping blankets.

The invention will be more fully illustrated by the following examples but it is to be understood that its scope is not to be limited to the specific embodiments shown.

A preferred vinyl ether used in the examples is 3,4- dihydro 2H pyran-Z-methyl-(3,4-dihyd-ro-2H-pyran-2- carboxylate) of the following formula:

It may be prepared by the self-condensation of acrolein dimer (2-formyl-3,4-dihydro-2H-pyran) in the presence of about 0.3% of aluminium isoproxide, the reaction temperature being held at 45 C. for 6 hours. A purified product may be obtained by flash distillation in a falling film still at C. under vacuum, but satisfactory foams can be obtained with the undistilled product.

9 EXAMPLE 1 200 g. of 3,4-dihydro-2H-pyran-2-methyl-(3,4-dihydro- 2H-pyran-2-carboxylate) were mixed with 50 g. of trichloromonofluoromethane, 2.5 g. of a boron trifluoride solution made up from BF etherate containing 49% BE, diluted to 10% BF with diethylene glycol, and 5.0 g. of siloxane oxyalkylene copolymer type silicone surfactant.

The induction period before foaming for this mixture was about 60 secs., and the mixture was stirred vigorously until just before foaming began. It was then poured rapidly into a mold and reacted to yield a rigid foam having a density of about 2.5 lbs./ cu. ft.

EXAMPLE 2 In an experiment similar to that of Example 1, 5.0 g. of the BF etherate solution was used. The induction period was shortened to 25 secs. and a foam having the same density was obtained.

The mixture had a 90 secs. induction period and foamed to a rigid foam of very even structure :and density of about 2.5 lbs./cu. ft.

EXAMPLES 5 TO 13 TABLE I Siloxane Boron trioxyalkylene Trichlorofluoride Induction Rise Period, Example Vinyl Ether copolymer monofluoroin diethylene Period, see. sec. Height, inches type silicon methane, g. glycol, ml. surfactant, g.

5 3,4-dihydro-2H-pyran-2-methyl-(3,4 0.5 5 1.0 80 8 8. 75

gghydro-2H-pyran-2-carb oxylate) g. 6 Bis-(3,4 dlhydro-2H-pyran-2-methyl) 0. 5 4 15 sucelnate: g. 7 Bls-(3,4-dihydro2H-pyran-2-methyl) 0.5 5 0.5 90 20 8 adipate: 20 g.

Bis-(3,4-dihydro-2H-pyran-2-methyl) azelate: 8. 20. 0.5 5 0. 6 165 15 5. 5 9 20 0. 5 5 1. 0 95 10 6. 75

Bis-(3,4- 'hydro-2H-pyran-2-methyl):

sebacate: 10 20 g.. 0.5 5 1 0 110 10 6. 75 11 20 g 0.5 5 l 4 95 10 5. 5 12 Bis-6,4 'hydro-2H-pyran-2-methyl) 0. 5 5 1 0 20 phthalate: 20 g. 13 Bis-(3,4-dihydro-2H-pyran-2-methyl) 0.3 3 0 6 165 45 4. 5

tumarate: 10 g.

1 0.75 m1. 0! 10% BF; in polypropylene glycol MW. 2025 dissolved in 1.0 g. trlchloromonofiuoromethane.

The induction period was 30 secs., and the product was a rigid foam having a density of 2.4 lbs/cu. ft.

EXAMPLE 4 The following mixture was prepared:

G. 3,4-dihydro-2H-pyran-2-methyl (3,4-dihydro-2H- pyran-Z-carboxylate) 14 Dioctyl phthalate plasticizer 6 Trichloromonofluoromethane 7 10% BF in glycol 2 Siloxane oxyalkylene copolymer type silicone surfactant 15 EXAMPLES 14 to 18 A series of five foams were prepared derived from crude 3,4 dihydro 2H pyran 2 methyl (3,4 dihydro- 2H-pyran-2-carboxylate) admixed with an additional vinyl ether and employing different catalyst systems. The following are the proportions of the mixture employed.

Gr. Crude 3,4-dihydro-2H-pyran-2-methyl-(3,4-dihydro- ZH-pyran-Z-carboxylate) 20 Additional vinyl ether 5' Trichloromonofluoromethane 5 Siloxane oxyalkylene copolymer type silicone surfactant 0.1

Catalyst as specified in Table II.

The ingredients were mixed together in a 250 ml. paper cup. The foams are described in Table II. The catalyst concentration is expressed as percentage by weight of the active ingredient.

The boron tri- TABLE 11 Amount of Induction Height of Example Additional Vinyl Ether Catalyst catalyst drops Period, Foam, inches seconds 14 Divinyl ether of polypropylene glycol of mo- Fluoboric acid, 48%50% in water.-- 3 5 8 iecular weight 425. Divinyl ether of polypropylene glycol of mo- Fluoboric acid, 5% in diethylene glycol. 25 255 4 lecular weight 425. 16 Trivinyl ether of propoxylated phenol-alde- Fluoboric acid, 48%-50% in water-.. 2 5 2 hyde condensate of molecular weight 440. 17 Tetravirlllyl either oi. polypropoxylated pen- Fluoboric acid, 48%50% in water 3 taeryt rito 18 Tetravinyl ether of polypropoxylated pen Fluoantimonic acid (HSbFs) 65% in 4 taerythritol. water.

1 Very fast.

EXAMPLES 19 TO 27 EXAMPLES 28 TO 28f A series of nine foams were prepared each of the fol- A series of seven foams were prepared containing trislowing composition: (3,4-dihydro-2H-pyran-2-methyi) phosphate alone and in G. admixture with another vinyl ether using the following Vinyl ether procedure. The phosphate the additional vinyl ether, Trichloromonofluoromethane 5 when present, the siloxane oxyalkylene copolymer type Siloxane oxyalkylene copolyrner type silicone sursilicone surfactant and the trichloromonofiuoromethane factant 0.1 5 foaming agent were mixed together. The boron triflu- Catalyst, as specified in Table III. oride catalyst Was then added with additional stirring and The above ingredients were mixed in a 250 mi. paper E3; 233 55535 1323 aig 3; 155 9 2; p g cup and the induction period and rise time of the resulting ht of the f Were measured Th To e foams were measured. The description of the foams is resultin foam are describedin Table a T given in Table Th6 catalyst concentration is ex- 30 catal st confentrati n is ex ressed as wei ht ercent f pressed as percentage by weight of the active ingredient. y P g p 0 TABLE III Amount of Induction Height oi' Example Additional Vinyl Ether Catalyst catalyst drops Periog, Foam, inches SGCOH S Bis-(3{A-dihydrOZH-pyranQ-methyl) suc- Fiuoboric acid, 48%50% in water"..- 3 5 7 cma e. Bis-(3,4-dihydIoZH-pyran-Z-methyI) adipate- Fluortmtimonic acid, (HSbFQ) 65% in 5 5 6 W3. er. Bis-(3,4-dihydro-2H-pyran-2-methyl) azelate Phosphorus pentafluoride 10.5% in 20 9O 3% dicthylene glycol. .do do 10 180 2 Bis-(3,4dihydro-2H-pyran-2-methyl) scbacate Fluoboric acid, 48%50% in water- 3 2O 4 Divinyl ether of polypropylene glycol of mo- Antimony fluoborate, %-43% in 5 5 lecular weight 425. water. -do 2 5 4 .do Lead fiuoborate, 50%-52% in water 15 380 4 Tetravinyl ether of polypropoxylated pen- Fluoboric acid,4B%-50% in water 2 180 3 taerythritol.

the boron trifiuoride, present as the etherate, in diethylene glycol.

TABLE IV Tris-(3,4-dihy- Slloxane Boron tridm-zfl-pyranoxyalkylene Trichlorofluoride, 10? Induction Rise time Height 0! Example 2-methyl) Additional Vnyl Ether copolymer monofluorolndiethyl- Period, sew. foam, phosphate, g. type surmethane, g. eneglycol, ml. secs. inches Iaetant, g.

3,4-dihydro-2H-pyran-2-methyl-(3-4- dihydro-ZH-pyran-2carboxylate): 10 0.5 5 1.5 50 90 6.5 10 0.5 5 2.5 35 6.25

5 10 g 0.5 5 2.0 25 25 4. 5 5 Bis-(3,-dihydro-2H-pyran-2-methyl) 0.5 5 1.5 30 30 3.5

azclate: 10 g.

13 EXAMPLES 28g TO 28k The following series of foaming compositions were prepared containing bis-(3,4-dihydro-2H-pyran-2-methyl) terephthalate and an additional vinyl ether using the fol- 14 to seconds. The induction period, the period of rise of the foam and the height of the foam after rise were measured. The compositions and characteristics of the resulting foams are shown in Table V.

lowing procedure. The two vinyl ethers, the surfactant 5 X l M and foaming agent were mixed together and then the E PLES 43 To 45 boron trifluoride catalyst was added with additional stir- A eries of three foams were prepared containing a high ring. The compositions was then poured into a 250 ml. viscosity epoxidized polyolefin (0x1ron 2000), the tr paper cup and the induction period the rise time and amide of the cyclic tricarboxylic acid which is the cyclic height of the resulting foams were measured. The de- 10 trimer of unsaturated fatty acids containing 18 carbon scription of the foams is given in Table IV(a). atoms in the molecule (Emery 31621-0 trimer acid) TABLE IV(a) Bis-(3,4-dihy- Siloxane Boron tridro-2H-pyranoxyalkylene Trichlorofluoride, 10% Induction Rise time Height of Example Z-methyl) AdditionalVinyl Ether copolymer monofluoroindiethyl- Period, secs. foam, terephthalate, type silicone methane, g. eneglycol, ml. secs. inches g. surfactant, g.

28g 10 3,4-dlhydro-ZH-pyren-Q-methyl-(3,4- -0.5 5 1.5 45 15 10.75

iihydroQH-pyran-Z-carb oxylate) Bis(,4-dihydro-2H-pyran-2-methyl) adipate: 10 10 g 0.5 5 1. 5 15 10. 75 15 15 g 0. 5 5 1. 5 70 10 9 10 Bis (3,4-dihydro-ZH-pyran-Z-methyl) 0.5 5 1.5 70 15 8.5

azelete: 10 g. 10 Bis-(3,4-dihydro-2H-pyran-2-methyl) 0.5 5 1.5 85 15 8.75

sebacate: 10 g.

EXAMPLES 29 TO 42 and 3,4 dihydro-ZH-pyran-Z-methyl-(3,4-dihydro-2H-pyran-Z-carboxylate) using the following procedure. The A genes of fourteen foams were prepared conta1n1ng vinyl ether, the epoxidized polyolefin, the triamide, the the. fliamide 0f the cycllc trlcarboxlfllc acid w 15 the siloxane oxyalkylene copolymer type silicone surfactant cycllc trime1 0f 'llllsatllfatfid fatty aclds contalmng and the trichloromonofiuoromethane foaming agent were bon ato s the 11101661116 f W Tflmel mixed together. The boron trifluoride catalyst was then Acid) and (hfiel'ent vlnyl f g the fO11W1I1g p added and the mixture was poured into a 25 0 ml. paper d re. The vlnyl ether. the tnarmde, the sllvxane y y cup and stirred for 1 0 to 15 seconds. The induction peene copolymer type silicone surfactant and the trichloromonofluoromethane foaming agent were mixed together. The boron trifi-uoride catalyst was then added and the mixture was poured into a 250 ml. paper cup and stirred for riod, the period of rise of the foam and the height of the foam after rise were measured. The compositions and characteristics of the resulting foams are shown in Table VI.

TABLE V Siloxane oxy- Boron tri- Cyclic trialkylene co- Trlchlorofluoride 10% Induction Rise Height, Ex. Vinyl Ether carboxylic polymer type monofluoroin diethylene period, period, in.

acid amide, g. silicone sugmethane, g. glycol, ml. sec. sec.

factant, g.

3, 4-dihydr0.-2H-pyran-2-methyl- (3, 4-dihydro-2H-pyran-2-earboxylate):

Bis-(3, 4dihydro-2H-pyr methyl) adipate:

Bis-(3, 4-dihydro-2H-pyran-2- methyl) azelate:

20 g 1 0. 5 5 2. 0 180 20 5. 25 20 g 3 0. 5 5 3. 5 210 70 7. 5 20 g 5 0. 5 5 5. O 180 60 5 Bis-(3, 4dihydro-2H-pyran-2- V g methyl) sebacate: 41 2O 1 0. 5 5 2. 0 20 4 42 20 g 3 0. 5 5, 3. 5 200 70 7 TABLE VI 3,4-dihydro- Siloxane Boron tri- 2H-pyran-2- High Cyclic oxyalkylene Trichlorofluoride Induction Rise Example methyl-(3,4- viscosity tricarboxylic copolymer monofluoro- 10% in Diperiod, Period, Height,

dihydro-2H- epoxidized acid amide, g. type silicone methane, g. ethylene sec. sec. in. pyran-2-carpolyolefin, g. surfactant, g. glycol, ml. boxylate), g.

15 EXAMPLES 46 TO 53' A carbamate igroup-containing prepolymer was prepared in the following manner. 1,5-pentanediol (52.1 g., 0.5 mole) was added dropwise with stirring to toluene- 1'6 and different vinyl ethers using the following procedure. The vinyl ether, the car-bamate group-containing prepolymer, the siloxane oxyalkylene copolymer type silicone surfactant and the trichloromonofiuoromethane foaming agent were mixed together The boron triflu- I 1 5 f i g g 3 8 T$ gg oride catalyst was then added and the mixture was poured A Ween b I 1 d Th f into a 250 ml. paper cup and stirred for 10 to 15 seconds. 1 opaqufe e g washo f e m g The induction period, the time of rise of the foam and P rumto t e i 6 Presence 0 the height of the foam after rise were measured. The fee lsoqyanae .groups no y mxy 10 compositions and characteristics of the resulting foams A series of eight foams were prepared containing the are shown in Table VIII. above described carbamate group-containing prepolymer and difierent vinyl ethers using the following procedure. EXAMPLE 61 The vinyl ether, the carbamate group-containing p re- The following two mixtures were prepared: polymer, the siloxane oxyalkyiene copolymer type s1l1- Mixture A cone surfactant and the trichloromonofluoromethane l foaming agent were mixed together. The boron trifiuoride Crude 3,4-dihydro-2H-pyran-2-methyl-(3,4dihydrocatalyst was then added and the mixture was poured into ZH-pyran-Z-carboxylate) 200 a 250 ml. paper cup and stirred for to seconds. 3,4-dihydro-2H-pyran 50 The induction period, the time of rise of the foam and Siloxane oxyalkylene copolymer type silicone surfacthe height of the foam after rise were measured. The tant 2.5 compositions and characteristics of the resulting foams Trichloromonofluoromethane 50 are given in Table VII. Trimethoxyboroxine 20 TABLE VII Carbamate Siloxane Boron group oxyalkylene Trichlorotritiuoride Induction Rise Height, Ex. Vinyl Ether containing copolyrner mouofiuoro- 10% in diethylperiod, period, in.

prepolymer, g. type silicone methane, g. glycol, ml. see. sec.

surfactant, g.

3,4-dihydro-ZH-pyran-Z-methyl- (3,4-dlhydro-2H-DY D-2-carboxylate):

1 0.5 5 1.5 210 15 7. 75 4 0. 5' 5 2. 0 10 11.25 4 0.5 5 1.5 8 5 9.75 s 0.5 5 1.5 50 30 11.5 20g 12 0.5 5 1.5 120 11.25 Bis-(3,4-dihydro-2H-pyran-2- 6 0. 5 5 1. 5 20 10 9. 75

methyl) adipate: 20 g. 52 Bis-(3,4-dihydro-2H-pyran-2- 6 0.5 5 1.5 60 20 9.75

methyl) azelate: 20 g. 53 Bis-(3,4-dihydro-2H-pyran-2- 5 0.5 5 1.5 15 9 methyl) sehacate: 20 g.

TABLE VIII Garbamate Siloxane Boron group oxyalkylena Trichlorotrifluoride Induction Rise Height, Ex. Vinyl Ether containing copolymer monofluorw 10%indiethylperiod, period, in.

prepolymer, type silicone methane, g. one glycol, ml. sec. sec.

g. surfactant, g.

3,4-dihydro-2H-pyran2-methyl (3,tdihydro-2H-pyran-2-carboxylate): 54 20 1 0.5 5 1. 5 90 30 s. 25 55 7. 5 o. 5 5 2. o 90 so 7. 5 55 2 0. 5 5 1. 5 100 35 9. 25 57 20 g 4 0. 5 5 2.0 15 30 10. 25 58 Bis-(3,4-dihydro-2H-pyran-2- 4 0.5 5 2.0 so so 8 methyl) adlpate: 20 g. BiS-(3,4dihydro-2H-pyran-2- methyl) sebaeate: 59 20 g 4 0. 5 5 2. 0 25 10 5. 25 5o 20 g 1 0. 5 5 1. 5 200 25 5. 5

EXAMPLES 54 TO 60 A carbamate group-containing prepolymer was prepared in the following manner. Toluene-2,4-diisocyanate (87 g., 0.5 mole) was added dropwise with stu'rmg to Mi B 1,5-pentanediol (104.2 g., 1 mole). The temperature was kept between 60 C. and 65 C. by occasional cooling. Boron trifluoride (10%) in diethylene glycol) 15 The resulting prepolymer was a very viscous, colourless glass. The infrared spectrum of the prepolymer showed the presence of free hydroxyl groups but no isocyanate groups.

A series of seven foams were prepared containing the Mixture B was added to Mixture A with mechanical stirring. After 10 seconds of mixing, the composition was poured into a mould and foaming occured after 20 seconds. A dark coloured rigid foam resulted which above described carbamate group-containing prepolymer had a core density of 1.2 lbs./cu./ft.

17 1% EXAMPLE 62 EXAMPLE 69 The following two mixtures were prepared: A monoethylenically unsaturated compound was prepared as follows: 0.75 gram of p-toluenesulphonic acid Mixture A was dlssolved in 130 grams of Z-ethylhexanol. This solucrude 3,4 dihydro 2H pyran 2 methy1 (34 dihydro tion was added to 225 grams of distilled 3,4-drhydro-2H- ramzcarbox late) 200 pyran 2 methyl (3,4 drhydro 2H pyran-Z-carboxy ylate) and the mixture heated for 2 hours on a steam Z'ethoxy'sAdlhydro'zH'pyran 100 bath Afte thi ti th react n rodu t wa brown Siloxane oxyalkylene copolymer type silicone surfac- I r S me e c s a l 10 T he following two mixtures were then prepared- Trichloromonofiuoromethane 50 Mixture B Mixture A Boron trifluoride (10% in diethylene glycol) 10 3 4 dih dm 2H ran 2 meth 3 4 dih p-Toluene sulphonic acid (20% in ethyl acetate) 30 pyramacarboxylatlg 10 Mixture B was added to Mixture A with mechanical Monoethylenically unsaturated P 10 stirring. After 10 seconds of mixing the composition Sfloxane oXyalkylene copolymer yp slhcone was poured into a mould and foaming occurred after iactaflt 17 seconds. A dark coloured rigid foam resulted which TflchloromOIlOflllOfOmethaIle 4 had a core density of 2.4 lbs./cu.ft. 20

zxture B 'EX AMPLE 63 Boron trifluoride 10% in diethylene glycol 1 The followmg two mlxfures were Prepared Mixture A was added to Mixture B with rapid stirring. Mixture A After 65 seconds foaming commenced. A light brown rigid foam was formed. Crude 3,4-dihydro-2H-pyran-2-methyl-(3,4-dihydro- 2H-pyran-2-carboxylate) 340 EXAMPLES 70 To Y y 'y ether 60 A series of five foams were prepared containing di-(2- 5110x3111? oxyalkylene p y y'p 811N011e Surfacethylhexyl)maleate and different vinyl ethers using the tam 2 following procedure. The vinyl ether, d1-(2-ethylhexyl) Mixture B maleate, the siloxane oxyalkylene copolymer type silicone Boron t ifl id 48% as ethemte 12 surfactant and the trichloromonofiuoromethane foaming Trichloromonofluoromethane 50 agent wer; mixgg together. The boron tnfluoride cata- Mixture B was added to Mixture A with mechanical ,253 z s g gf 22 i igg l z stirrlrgcg. Aftgr 5 sfiggndsdoffgnmrng t gl lzz ii gf e g induction period, the period of rise of the foam and the In 0 an amln m en e height of the foam after rise were measured. The coml A hght coloured foam of fine texture and havlng positions and characteristics of the resulting foams are a density of 2.0 lbs/cu. ft. resulted. Shown in Table EXAMPLES 64 TO 68 EXAMPLE 75 i o o 0 t 2H pyran 2 methyl-(3,4-d1hydro-2H-pyran-Z-carboxwmg In S G ylate), the monoethylenically unsaturated compound, the surfactant and the trichloromonofluoromethane foaming git i? f i 25. hate agent was prepared. To this mixture the boron trifluog a lpa e ride catalyst was added while stirring with a mechanical y exy ma sate -77 5 stirrer. After 10 seconds the composition was poured Slloxane Oxyalkylene copolymer type slhcone into a mould. In Table IX the foaming compositions factant and the resulting foams are described. Tnchloromonofluor'omethane 5 TABLE IX Crude 3,4-dihydro- Siloxane 2H-pyran-2-methy1 Mono ethylenically oxyalkylene type Trichlorornono Boron trifluoride Induction Density, Example (3,4dihydro-2H- unsaturated compound silicone fluoromethane, g. 10% in diethylene period, lbs/cu. ft.

pyrarligaca'boxysurfactant, g. glycol, g. sees.

64 200 Dibutyl maleate, 100 g 1 50 10 320 3. 7 65 20o Vinyl stearate, g 1 50 7 50 2. 5 s5 400 Styrene, 100 g 1 110 is 225 3.1 67 400 l-decene, 2 110 20 175 1. 2 68 400 n-Butyl acrylate, g 2 8 170 1. 9

TABLE X Di-(Zethyl- Siloxane Trichloro- Boron trifiu- Example Vinyl Ether hexyl) oxyalkylene monofiuorooride 10% in Induction Rise period, Height,

maleate, g. copolymer type methane, g. diethylene period, sec. sec. in.

surfactant, g. glycol, ml.

70 3,4-dlhydro-2H-pyran-2-methy1- 5 0.5 5 0.5 260 40 9.5

(3,4-dihydro-2H-pyran-2carboxylate), 20 g. 71 Bis-(3,4-dihydro-2H-pyran-2- 5 0.5 5 1.5 60 10 7.25

methyl) adipate, 20 g. 72 Bls-(3,4-dihydro-2E[-pyran-2- 5 0.5 5 1.5 85 10 7.25

methyl) succinate, 20 g. 73 Bis-(3,4-dlhydro-2H-pyran-2 5 0.5 5 1.5 10 4.5

methyl) azelate, 20 g 74 Bis-(3,4-dihydro-2H-pyran-2- 5 0.5 5 1.5 15 4 methyl) sebacate, 20 g.

19 and then adding with additional stirring 1.5 ml. of a solution containing 10% by weight of boron trifluoride in diethylene glycol. The composition was poured into a 250 ml. paper cup where after an induction period of 50 seconds it rose for 15 seconds to form a foam 3.5 in.

0.1 g. of siloxane oxyalkylene copolymer type silicone surfactant using a high speed stirrer. After 2 minutes of Mixture AContinued G.

Siloxane oxyalkylene copolymer type silicone surfactant 1 Trichloromonofluoromethane 50 Trimethoxy boroxine I Mixture B Boron trifluoride 10% in diethylene glycol 6 Mixture B was added to Mixture A with mechanical stirring. After 5 seconds of mixing, the composition was poured into a mould. Foaming commenced after 2.0 seconds. A light coloured foam of fine texture and having a density of 2.8 lbs/cu. ft. resulted.

stirring 2 g. of trichloromonofiuoromethane and 0.1 g. of y a solution containing 10% by weight of fluoboric acid in EXAMPLE diethylene glycol were added. The mixture was poured A polymerlzable monoethylemcally unsaturated cominto a mould where it foamed to form a white friable POImd Was P p as follows! of P40111511e foam. phonic acid was dissolved in 130 g. of Z-ethylhexanol.

EXAMPLES 77 TO 82 This solution was added to 225 g. of distilled 3,4-dihydro- 2H pyran 2rnethyl-(3,4-dihydro-2i-I-pyran-2rcarboxyi is gf f fgj gfig g gfggi g ia;$33: late) and the mixture heated for 2 hours on a steam 2 met hy1 (3,4 dihydm 2H pyran 2 carboxylate) Phenol, After this time, the reaction product was a brown the monoethylenically unsaturated compound, the surfac- I tant and the trichloromonofluoromethane foaming agent The fallowmg two matures were then prepared' was first prepared. The boron trifiuoride catalyst was Mixture A 4 added to this mixture while stirring with a mechanical G.- stirrer. After 5 seconds the composition was poured into Ethylenically unsaturated compound 60 a mould. Table XI describes the foaming compositions 3,4 dihydro 2H-pyran-2-methyl-(3,4-dihydro-2H- and the resulting foams. pyranQ-carboxy-late) 126 TABLE XI Crude 3,4- Dihydro-ZH- Siloxane Boron tripyran-2- Mono ethylenically unsatuoxyalkylene fluoride 10% Trichloro- Induction Density, Example methyl (3.4- Phenel, g. rated compound copolymer in diethylene monofluoroperiod, see. lbs/cu. It.

dihydro-2H- type silicone glycol, g. methane, g.

pyran-Z- surfactant, g. carboxylate, g.

400 Dlbutyl maleate, 200 g 2 16 110 35 2.5 200 25 Styrene 75g 0.5 9 35 1.2 200 25 l-decene, g 1 10 55 35 2. 5 200 25 Lauryl vinyl ether, 50 g 1 6 55 12 3. 7 200 25 Vinyl stearate, g 1 4 55 35 2.6 400 60 n-Butyl acrylate, g 2 8 60 1. 9

EXAMPLE 83 2z2-di-p-hydroxyphenylpropane 14 The following two mixtures were prepared:

Siloxane oxyalkylene copolymer type silicone surfactant I Trichloromonofluoromethane 40 Mixture A G Mixture of polyvmylchloride and antimony oxide Crude 3,4-dihydro-2H-pyran 2-methyl-(3,4-dihydro- 5 (Nlax Flame'retardant A) 30 ZH-pyran-Z-carboxylate) 200 Mixture B iitiii'iiiiii iiiftfiifffif.3:3333;313:3333: Z8 Boron fluoride 10% in ethylene glycol 5 Siloxane oxyalkylene copolymer type silicone surfac- Mixture B was added to Mixture A with stirring. Afiter tant 1 55 an induction period of 30 seconds foaming commenced. Trichloromonofiuoromethane 50 The foam had a very fine texture, was light in colour, had a density of 2.9 lbs./ cu. ft. and was self-extinguishing b Mixture B ASTM 1692-59-T. Boron trifluoride 10% in diethylene glycol 3.8 60 EXAMPLE Mixture B was added to Mixture A with mechanical stirring. After 5 seconds of mixing the composition was poured into a mould. Foaming commenced after 20 seeonds. A white foam of fine texture and having a density of 2.5 lbs/cu. ft. resulted.

EXAMPLE 84 The following two mixtures were prepared:

Diethylene glycol-trimethylolpropaue maleate was prepared by heating under reflux at 1-60"- C. in toluene solution, one mole each of diethylene glycol, trimethylol propane and maleic anhydride. Heating was continued until the estenification reaction ceased to produce water.

A foaming composition containing the following in gredients was prepared:

Butanediol 1,4 bis-(3,4-dihydro-2H-pyran-2-yl) ether g 15 Mixture A 7 2:2-di-p-hydroxyphenyl propane g 5 G. Diethylene-glycol-trimethylolpropane m-aleate -g 5 Crude 3,4-dihydro-Zl-I-pyran-Zmethyl-(3,4-dihydro- Trichloromonofiuoromethane g 5 Q-H-pyran-Z-carboxylate) 200 Siloxane oxyalkylene copolymer type silicone surfac- Novolak resin 50 mm g 09.1 Styrene 50 75 Boron trifluoride, 10% in diethylene glycol ml.. 0.2

The first five ingredients were mixed for 10 seconds EXAMPLE 94 and the .boron trifluoride catalyst was then added with additional stirring. After an induction period of 2.7 The followmg two m1Xt ureS were prepared minutes a soft foam was obtained. M re A G. EXAMPLE 87 Crude 3,4-dihydro-2H-pyran-2-rnethyl-(3,4-dihydro- The benzoate of 2-hydroxyrnethyl-3,4-dihydro-2H- ZH-pyran-Z-carboxylate) 200 py-ran was prepared by esterification of 3,4-d-ihydro-2H- Dibutyl maleate 50 pyran-Z-methanol with benzoyl chloride. Siloxane oxyalkylene copolymer type silicone sur- A foaming composition containing the following infactant 5 gredients was prepared: Trichloromonofiuoi-omethane 50 Butanediol 1,4 bis-(3,4-dihydro-2H-pyran-2-yl) MixtureB ether g P olypr-opylene glycol molecular weight 2025 200 g g g z 'Z5f 'fi' 5 15 Trichloromonofluoromethane 50 e enzoate o y roxymet y 5 Y 5 Boron trifluOI-ide 75 Pyran 48% as etherate p-toluenesulphonic laCid, 10% in Trichloromonofluoromethane g 5 6th 1 y acetate 10 Siloxane oxyalkylene copolymer type silicone surfac- Itant 0.1 Mixture B was added to Mixture A with mechanical Boron .t ifl id 10% in methylene glycol 1 3 stirring. After 5 seconds of mixing, the composition was Th fi fi c d f 10 d poured into a mould. Foaming commenced after 61 e rst ve 9 .lents were mlxe or Sewn. S seconds. A light coloured foam of fine texture and havand the boron trifluoride catalyst was then added with in d g a ensity of 2.7 lbs/cu. ft. resulted. additional stirring. After an induction period of 42 seconds a rigid foam with hard skin was obtained. EXAMPLE 95 Th 11 v EXAMPLES 88 To 92 e fo owin two mixtures were prepared Mixture A A series of five foams were prepared containing 2:2-di- G. p-hydroxyphenyl propane, di-(Z-ethyl-hexyl) maleate and Crude 3,4-dihydro-2H-pyran-2-methyl-(3,4-dihydrodifferent vinyl ethers using the following procedure. The 2H-pyran-2-carboxylate) 200 vinyl ether, 2:2-di-p-hydroxyphenyl propane, di-(Z-ethyl- Styrene 50 hexyl) maleate, the siloxane oxyalkylene copolymer type Siloxane oxyalkylene copolymer type silicone sursilicone surfactant and the txichloromonofluoromethane factant 5 foaming agent were mixed together. The boron trifluoride Tnchloronionofluoromethane catalyst was then added and the mixture was poured into t B a 250 ml. paper cup and stirred for 10 to 15 seconds. The We induction period, the period of rise of the foam and the Polypropylene glycol molecular weight 2025 200 height of the foam after rise were measured. The com- Trichloromonofiuoromethane 50 positions and characteristics of the resulting foams are 40 Boron trifluoride 48% as ethei-ate 7.5 shown in Table XH. p-Toluenesulphonic acid 20% in ethyl acetate 5 TABLE XII 2:2-di-p- Siloxane Boron tri- Induchydroxy- Di-(Q-ethyl- Oxyalkylene Trichlorofluoride tion Rise Height, Ex. Vinyl Ether phenyl hexyl) copolymer monofluoro- 10% in (11- period, period, in.

propane, g. maleate, g. type surmethane, g. ethylene see. sec.

faetant, g. glycol, ml.

88 3,4-dihydro-ZH-pyran-Z-methyl- 5 5 0.5 5 0.5 30 20 9. 75

(3,4-dihydro-2H-pyran-2- carboxylate), 20 g. 89 Bls-(3,4dihydr0-2H-pyran-2- 5 5 0.5 5 0.5 40 25 7.75

methyl) adipate, 20 g. 90 Bis-(3,4dihydr0-2H-pyran-2- 5 5 0.5 5 0.5 90 30 4. 75

methyl) succinate 20 g. 91 Bis-(SA-dihydro-ZH-pyran-Q- 5 5 0.5 5 0.7 80 10 3 methyl) azelate, 20 g. 92 Bis-(3,4dihydro-2H-pyran-2- 5 5 0.5 5 1.0 100 30 2.75

methyl) sebacate, 20 g.

EXAMPLE 93 The following foaming composition was prepared: Tetravinyl ether polypropoxylated pentaerythritol g 15 2:2-di-p-hydroxyphenyl propane g 5 The benzoate of 2-hydroXymethyl-3,4-dihydro-2H pyran g S Trichlorornonofiuoromethane g 5 Siloxane oxyalkylene copolymer type silicone surfactant g 0.1

Boron trifluoride, 2% in diethylene glycol ml 0.25

The first five ingredients were mixed together for 10 seconds and then the boron trifluoride catalyst was added with additional stirring. The composition foamed after an induction period of 36 seconds to produce a flexible soft weak foam.

Mixture B was added to Mixture A with mechanical stirring. After 5 seconds of mixing the composition was poured into a mould. Foaming commenced after 27 seconds. A dark coloured foam of fine texture and having a density of 2.4 lbs/cu. ft. resulted.

EXAMPLE 96 Mixture B poured into a mould. Foaming commenced after 64 sec- G. onds. A dark coloured foam of fine even texture and Boron trifiuoride 10% in polypropylene glycol 15 having a density of 1.7 lbs/cu. ft. resulted. p-Toluenesulphonic acid, 20% in ethyl acetate 10 Trichloromonofluoromethane 50 Th f n EAMPLE 99 d Mixture B was added to Mixture A with mechanical e 0 Owing two mlxfures were prepare stirring. After seconds of mixing, the composition Mixture A was poured into a mould. Foaming commenced after 50 G. seconds. A dark coloured foam was obtained which had Crlldfi y -py ny (3, 1 y r a density of 0.9 lbs/cu. ft. 10 'PY Y 200 Z-ethylhexyl acrylate 30 EXAMPLE 97 Siloxane oxyalkylene co olymer type silicone surfac- P Tho following two mixtures -were prepared: F 2 Trrohloromonofiuoromethane 30 Mixture A G. Mixture B Crude 3,4-dihydro-2H-pyran-2-methyl-(3,4-dihydno- ZH-pyran-Z-carboxylate) 200 D1 y yp y phthalate 100 lsobutyl vinyl ether 3 Trichloromonofluoromethane 50 Polyol condensate derived from pent-aerythritol and Boron trlfiuonde f etheriite 3 propylene oxide (pl l PER 500 100 p-Toluenesulphonic acid, 20% in ethyl acetate 6 Siloxane oxyalkylene copolymer type silic ne u Mixture B was added to Mixture A with mechanical tam 1 stirring. After 15 seconds of mixing, the composition Mixture B was poured into a mould. Foaming commenced after 70 G seconds. A dark coloured foam of fine texture and hav- Bomn trifluoride 48% as etherate mg a density of 1.9 lbs/cu. ft. resulted. p-T oluenesulphonic acid 10% in ethyl acetate 5 EXAMPLES 100 TO 104 Tnc'hloromonofiuoromethane A series of five foams were prepared containing poly- Mixture B was added to Mixture A with mechanical 30 propylene glycol of molecular weight of 2025, di-(Z-ethylstirring. After 5 seconds of mixing, the composition was hexyl) male-ate and different vinyl ethers using the followpoured into a mould. Foaming commenced after 28 seeing procedure. The vinyl ether, polypropylene glycol onds. A dark oolonred foam of fine even texture and and di-(Z-ethylhexyl maleate, the siloxane oxyalkylene having a density of 1.9 lbs/cu. ft. resulted. copolymer type silicone surfactant and the trichloromono- TABLE XIII Siloxane Boron tri- Polypropyl- Dl-(Z-ethyloxyalkylene Trichlorofluoride Indue- Rise Height, Ex. Vinyl Ether ene glycol hexyl) copolymer monofluoro- 10% in tlon period, in.

MW. 2025, g. maleate, g. type silicone methane, g. diethylene period, see.

surfactant, g. glycol, ml. see.

100 3,4-dihydro-2H-pyran-2-methyl- 7 5 0.5 5 1.5 230 20 5. 75

(3,4-dihydro-2H-pyran-2-carboxylate, 20 g. 101 Bis-(3,4-di ydro-2H-pyran-2- 7 5 0.5 5 2.0 85 10 4.25

methyl) adipate, 20 g. m9 Bis-(3,4dihydro-2H-pyran-2- 7 5 0. 5 5 2. 0 00 10 c. 25

methyl) succinate, 20 g. 103 Bis- 3,tdih dm2H- mn-2- 7 5 0.5 5 2.0 150 15 a. 25

methyl) azelate, 20 g. 104 Bis-(SA-dihydro-ZH-pyranQ- 7 5 0. 5 5 2. 0 160 15 2. 75

methyl) sebacate 20 g.

EXAMPLE 98 fluormet-hane foaming agent were mixed together. The bonon trifiuoride catalyst was then added and the mixture A d: The following two mlxfums were Prepare was poured lnto a 250 ml. paper cup and stirred for 10 Mixture A to 15 seconds. The induction period, the period of rise of G. the foam andthe height of the foam after rise were Crude 3,4-d1hydro-ZH-pyran-Z-methyl-(3,4-d hydromeasured. The compositions and characteristics of the 2H-pyran-2-carboxylate) 00 resulting foams are shown in Table XIII. 14mm 30 EXAMPLES 105 TO 110 Polyol condensate derived from pentaerythritol and propylene oxide (Pluracol P.E.P. 500) 100 A mixture was prepared consisting of crude 3,4-dihy- Siloxane oxyalkylene copolymer type silicone surfacdro 2H-pyran-2-methyl-(3,4-dihydro-2H-2-carboxylate),

tant l the monoethylenica-lly unsaturated compound, the mate- Mixmre B rial containing one or more epoxide groups per molecule,

G the siloxane oxyalkylene copolymer type silicone surv p factant, the trichloromonofiuoromethane foaming agent 958;;323F53 iggi g$ gg i ;ff gg g"' and the trimethoxy boroxine catalyst. The boron tri- PF. hl pofluomm than: y 5 fluoride catalyst was added to this mixture while stirring nc oromon e 7 with a mechanical stirrer. After 10 seconds the com- Mixture B was added to Mixture A with mechanical position was poured into a mould. Table XIV describes stirring. After 5 seconds of mixing, the composition was the foaming compositions and the resulting foams.

TABLE XIV Crude 3,4- Siloxane dihydro2H- Monoethylenioxyalkyl- Triehloro- 10% boron pyran-2- cally unsaturated ene monotrifluoride Trimeth- Induction Density, Ex. methyl-(3,4- Epoxlde compound polymer fiuoroin dlethyloxy boroxtime, 1bs./ dihydro-2H- type silimethane, ene glycol, ine, g. see. cu. ft. pyran-2-carcone surg. g. boxylate, g. faetant, g.

105 200 Reslnous condensate of epi- Butyl vinyl 0. 5 50 7 1 23 2. 9

chlorohydrin and 2:2-di-pether, 50 g. hydroxyphenyl propane, 50 g. 106 200 Epichlorohydrin, 50 g Styrene, 30 g 0. 5 50 8 95 3. 4 107 200 Poly allyl glyoidyl ether, 50 g. Dgbutyl maleate, 1 50 6 75 2. 7

0 g. Y 108 200 Poly allyl glycidyl ether, 50 g. Vi15yl propionate, 1 50 7 90 1. 9

g. 109 200 Resinous condensate of epil-deeene, 25 g 1 50 6 46 1. 9

chlorohydrin and a phenol formaldehyde resin, 50 g. 110 200 As Example 5, 50 g n-zla3utyl aorylate, 1 50 6 92 2. 4

These foams have good tough skins and are light coloured and of fine cell structure.

EXAMPLES 111 to 117 EXAMPLE 1 19 The following foaming composition was prepared:

Butanediol-1,4-divinyl ether g A series of seven foams were prepared containing a 25 The benzoate of 2-hydroxymethyl-3,4-dihydro-2H- high viscosity epoxidized olefin (Oxiron 2000), di-(Z- pyran g 5 ethylhexyl) maleate and different vinyl ethers using the Low molecular weight resinous condensate of epifollowing procedure. The vinyl ether, the epoxidized chlorohydrin and 2:2-di-p-hydroxyphenyl propolyolefin, di-(Z-ethylhexyl) maleate, the siloxane oxypane g 10 alkylene copolymer type silicone surfactant and the tri- 3O Trichloromonofluoromethane g 5 chloromonofiuoromethane foaming agent were mixed to- Siloxane oxyalkylene copolymer type silicone surgether. The boron trifluoride catalyst was then added factant g 0.1 and the mixture was poured into a 250 ml. paper cup and Boron trifluoride, 5% in diethylene glycol ml 0.15 i g 3 sefconds i g g the The first five ingredients were mixed together for 10 gi g aii gg $2 z i zgg g 22? 35 seconds and then the boron trifiuoride catalyst was added ,3 i 1 S a V 2 wt additoal strn. After 11 nd to e o acteristics of the resulting foams are shown in Table XV. l h 1 n 1 n g a 1 uc 1 n p nod L TABLE XV Siloxane High Di-(2-ethyl oxyalkylene Tn'ehloro- Boron tri- Indue- Rise Ex. Vinyl Ether viscosity hexyl) copolyrner monofluorofluoride 10% tion period, Height,

epoxidized maleate, g. type methane, g. indiethylene period, see. in. polyolefin, g. silicone glycol, ml. see.

surfactant, g.

3,4-dihydro-2H-pyran-Z-methyl- (3,4-dihydro2H-pyran-2rearboxylate): 111 20g 5 5 0.5 5 0.5 10 30 2 112 20g 5 5 0.5 5 0.8 10 2o 4 113 Bis-(3,4-dihydro-2H-pyran-2- 5 5 0.5 5 1.0 10 10 6.25

methyl) adipate: 20 g. 114 Bis-(3,4-dihydro-2EI-pyran-2- 5 5 0.5 5 1.0 7 8.5

methyl) suceinate: g. 115 Bis-(3,4-dihydro-2H-pyran-2- 5 5 0.5 5 1.0 10 15 5.75

methyl) azelate: 20 g. 116 Bis-(3,4-dihydro-2Hpyran-2- 5 5 0.5 5 1.0 10 10 4.75

methyl) sebaeate: 20 g. 117 Bis-(3,4-dihydro-2H-pyran-2- 3 a 0.5 5 0.6 15 4. 25

methyl) fumarate: 10 g.

EXAMPLE 118 12 seconds the composition foamed to form a white The following foaming composition was prepared: flexible weak foam Butanediol-l,4-divinyl ether g 10 EXAMPLE 120 Diethylene glycol-trimethylolpropane maleate g 5 The foaming composition containing the following in- Low molecular Weight resinous condensation prodgredients was prepared:

not of epichlorohydrln and 2:2-d1-p-hydroxyphen- Butanediol 1,4 bis (3,4 dihydm 2H Pyran 2 y1) y propane --s-- 10 ether 10 gg ifi g gg gi 'gf 5 Low molecular weight resinous condensate of epigggfi OXy y me p ymer ype S one 0 1 chlorohydrin and 2:2-dip-hydroxyphenyl propane g 10 Boron trifluorrde, 5% 1n diethylene glycol ml 0.15 The benzoate of 2 hydrOXymethy1 3,4 dihydro 2H The first five ingredients Were mixed together for 10 pyran g 5 seconds and then the boron trifluoride catalyst was added Trichloromonofluoromethane g 5 with additional stirring. After an induction period of Siloxane oxyalkylene copolymer type silicone sur- 15 seconds the composition foamed to form a white flexfactant g 0.1 ible weak foam. Boron trifluoride, 20% in diethylene glycol ml 0.2

The first five ingredients were mixed together for 10 seconds and then the boron trifluoride catalyst was added with additional stirring. After an induction period of 1.4 minutes a rigid brittle foam was obtained.

EXAMPLE 121 The foaming composition containing the following ingredients was prepared:

Butanediol 1,4 bis-(3,4-dihydro-2H-pyran-2-yl)- ether g 10 Low molecular weight resinous condensate of epichlorohydrin and 2:2-di-p-hydroxyphenyl propane g 10 Diethylene glycol-trimethylolpropane maleate g 4 Trichloromonofluoromethane g 5 Siloxane oxyalkylene copolymer type silicone surfactant g 0.1

Boron trifiuoride, 20% in diethylene glycol ml 0.25

The first five ingredients were mixed together for seconds and then the boron trifluoride catalyst was added with additional stirring. After an induction period of 2.4 minutes of a dark foam was obtained.

EXAMPLE 122 The following foaming composition was prepared:

Divinyl ether of polypropylene glycol of molecular weight 425 g 10 Diethylene glycol-trimethylolpropane maleate g 2 Low molecular weight resinous condensation product of epichlorohydrin and 2:2-di-p-hydroxyphenyl propane g 12 Trichloromonofluorornethane g 5 Siloxane oxyalkylene copolymer type silicone surfactant g 0.1

Boron trifluoride, 10% in diethylene glycol ml 0.2

The first five ingredients were mixed together for 10 seconds and then the boron trifluoride catalyst was added with additional stirring. After an induction period of 6 seconds the composition foamed to form a flexible weak foam.

EXAMPLE 123 The following foaming composition was prepared:

Divinyl ether of polypropylene glycol of molecular weight 425 g 6 The henzoate of 2-hydroxymethyl-3.4-dihydro-2H- pyran g 4 Low molecular weight resinous condensation product of epichlorohy-drin and 2:2-di-p-hydroxyphenyl propane g Trichloromonofiuoromethane g 5 Siloxane oxyalkylene copolymer type silicone surfactant g 0.1

Boron trifluoride, 10% in diethylene glycol ml 0.15

The first five ingredients were mixed together for 10 seconds and then the boron trifiuoride catalyst was added with additional stirring. After an induction period of 12 seconds the composition foamed to form a flexible weak foam.

28 EXAMPLE 124 The following foaming composition was prepared:

The first five ingredients were mixed together for 10 seconds and then the boron trhluoride catalyst was added with additional stirring. The composition foamed to form a flexible weak foam.

EXAMPLE 125 The following foaming composition was prepared: Trivinyl ether of propoxylated phenolaldehyde condensate g 8 The benzoate of 2-hydroxymethyl-3,4-dihydro-2H- pyran g 4 Low molecular weight viscous condensate of epichlorohydrin and 2:2-di-p-hydroxy-phenyl propane g 12 Trichloromonofiuoromethane g 10 Siloxane oxyalkylene copolymer type silicone surfactant g 0.1

Boron trifiuoride, 10% in diethylene glycol ml 0.4

The first five ingredients were mixed together for 10 seconds and then the boron trifluoride catalyst was added with additional stirring. The composition foamed to form a flexible weak foam.

EXAMPLE 126 A foaming composition was prepared by mixing the following ingredients:

Tris- 3,4-dihydro-2H-pyran-2-methyl phosphate g 10 Bis- 3,4-dihydr0-2H-pyran-2-methyl) adipate g 10 High viscosity epoxidized polyolefin (Oxiron 2000) g 5 Di-(Z-ethylhexyl) maleate g 5 Siloxane oxyalkylene copolymer type silicone surfactant g 0.5 Trichloromonofiuoromethane g 5 and then adding with additional stirring 1.5 ml. of a solution containing 10% by weight of boron trifiuoride in diethylene glycol. The composition was poured into a 250 ml. paper cup whereafter an induction period of 5 seconds it rose for 20 seconds to form a foam 2.5 inches high. The foam was hard and tough with white skin and dark hard interior.

EXAMPLES 127 TO 134 A series of eight foams was prepared containing toluene-2,4-[bis-(3,4-dihydro 2H-pyran-2-methyl)carbamate] and the other additives using the following procedure. The toluene-2,4-[bis-(3',4'-dihydro-2H-pyran-2- methyl)carbamate], the additive, the siloxane oxyalkylene copolymer type silicone surfactant and the trichlorornonofiuoromethane foaming agent were mixed together. The boron trifluoride catalyst was then added and the mixture was poured into a 250 ml. paper cup and stirred for 10 to 15 seconds. The induction period, the time of rise of the foam and the height of the foam after rise were measured. The compositions and characteristics of the resulting foams are given in Table XVI.

TABLEXVI 'Ioluene2,4- Siloxane [bis-(3,4-dioxyalkylene Trichloro- Boroutri- Induction Rise Example hydro 2H- Additive copolymer monofluorofluoride 10% period, time, Height,

pyran-2- type silimethane, g. in diethylene secs. sees. inches methyl) carcone surglycol, m1.

bamate], g. iactant, g.

127 10 Bis-(3,4-dihydr-2H-pyran-2-methyl) 0. 5 1. 0 50 8 adipate: l0 128 10 Bis-(3,4-dihydro-2H-pyran-2-methyl) 0. 5 5 1. 0 10 70 7. 5

azelate: 10g. 129 10 Bis-(3,4-dihydro-2H-pyran-2-methyl) 0. 5 5 1. O 6O 7. 5

sebacate: 10 g. 3,4 dihydro-ZH-pyran-Z-methanol: 130 2O 10g 0.5 7 1.3 5 7 9.5 131 4.5 g 0. 5 5 0.8 10 45 7 3,4-dihydro-ZH-pyran-Zmethyl dihydro-ZH-pyran-Z-earboxylate): 10 10 g 0. 5 5 0. 6 35 95 6 10 0.5 5 1.0 35 60 10 10 0. 5 5 1. 3 20 v 10 EXAMPLE 135 The following ingredients:

3,4-dihydro-2H-pyran Z-methyl (3,4 dihydro-ZH- pyran-2-carboxylate) l4 Dioctyl phthalate 6 Siloxane oxyalkylene copolymer type silicone surfactant 2 Trichloromonofiuoromethane 7 /Cs2 HO (IJ 2 l wherein n is an integer having a value of at least two, R is a member selected from the group consisting of the hydrogen atom and the carboxaldehyde radical, and X is a linking group having a valence equal to n;

(B) an acidic catalyst capable of promoting the polymerization of said vinyl ether and selected from the group consisting of strong proton-donating acids and Lewis acids; and

(C) a foaming agent vaporizing at the temperature of polymerization of said vinyl ether.

2. A foamed cellular polymeric material as claimed in claim 1 wherein the foamable composition contains a material reactive with the ethylenic double bonds of its vinyl ether ingredient.

3. A foamed cellular polymeric material as claimed in claim 2 wherein the material reactive with the ethylenic double bonds of the vinyl ether ingredient of the foamable composition is a member selected from the group consisting of (D) compatible aliphatic and aromatic polyamides;

(E) compatible polycarbamates obtained by the condensaticn of polyisocyanates with aliphatic polyols;

(F) alpha, beta-monoethylenically unsaturated monomers copolymerizable with said vinyl ether;

(G) mixtures of (F) with compatible phenolic compounds; and

(H) mixtures of (F) with compatible aliphatic monohydric or polyhydric alcoholic compounds; and

(I) mixtures of (F) with compatible epoxidized materials containing at least one epoxide group per molecule.

4. A foamed cellular polymeric material as claimed in claim 3 wherein the proportions of the ingredients of the foamable composition are such that:

(D) the number of amido groups provided by the polyamide is less than 10% of the number of CH=CH groups provided by the vinyl ether;

(E) the number of carbamate groups provided by the polycarbamate is less than 75% of the number of CH=CH- groups provided by the vinyl ether;

(F) the number of ethylenic groups provided by the monoethylenically unsaturated compound is not more than three times the number of -CH=CH groups provided by the vinyl ether;

(G) the combined number of ethylenic and hydroxyl groups provided by the monoethylenically unsaturated and phenolic compounds, respectively, ranges from less than 75% of the number of CH=CH groups provided by the vinyl ether when the amount of phenolic compound exceeds that of monoethylenically unsaturated compound, to not more than three times the number of CH=CH groups provided by the vinyl ether when the amount of monoethylenically unsaturated compound exceeds that of phenolic compound;

(H) the combined number of ethylenic and hydroxyl groups provided by the monoethylenically unsaturated and alcoholic compounds, respectively, ranges from less than 75% of the number of CH=CH groups provided by the vinyl ether when the amount of alcoholic compound exceeds that of monoethylenically unsaturated compound, to not more than three times the number of CH=CH groups provided by the vinyl ether when the amount of monoethylenically unsaturated compound exceeds that of alcoholic compound; and

(I) the number of ethylenic groups provided by the monoethylenically unsaturated compound is not more than three times the combined number of CH=CH' and epoXide groups provided by the vinyl ether and epoxidized material, respectively.

5. A foamed cellular polymeric material as claimed in claim 1 wherein the foamable composition comprises 3,4-dihydro-2H-pyran-2-methyl-(3,4-dihydro-2H pyran- 2-carboxylate) as a vinyl ether ingredient.

6. A foamed cellular polymeric material as claimed in claim 2 wherein the foamable composition comprises 3,4-dihydro-2H-pyran-2-n1ethyl-(3,4-dihydro ZH-pyran- 2-carboxylate) as a vinyl ether ingredient.

7. A foamed cellular polymeric material as claimed in claim 3 wherein the foamable composition comprises 3,4 dihydro-2H-pyran-2-methyl-(3,4-dihydro-2H-pyran- 2-carboxylate) as a vinyl ether ingredient.

8. A foamed cellular polymeric material as claimed in claim 4 wherein the foamable composition comprises 31 3,4 dihydro-ZH-pyran-2-methyl-(3,4-dihydro-ZH-pyran- Z-carboxylate) as a vinyl ether ingredient.

9. A foamed cellular polymeric material as claimed in claim 1 wherein the foamable composition comprises bis(3,4-dihydrO-ZH-pyran-Z-methyl)phthalate as a vinyl ether ingredient.

10. A foamed cellular polymeric material as claimed wherein n is an integer having a value of at least two, R is a member selected from the group consisting of the hydrogen atom and the carboxaldehyde radical and X is a linking group having a valence equal to n; (B) an acidic catalyst capable of promoting the polymerization of said vinyl ether and selected from the group consisting of strong proton-donating acids and Lewis acids; and (C) a foaming agent vaporizing at the temperature of polymerization of said vinyl ether; and allowing the mixture naturally to self-expand into a foamed cellular polymeric material.

13. A process as claimed in claim 12 wherein there is incorporated into the expandable mixture a material reactive With the ethylenic double bonds of the vinyl ether.

14. A process as claimed in claim 13 wherein the material reactive with the ethylenic double bonds of the vinyl ether is a member selected from the group consisting of (D) compatible aliphatic and aromatic polyarnides;

(E) compatible polycarbamates obtained by the condensation of polyisocyanates with aliphatic polyols;

(F) alpha, beta-monoethylen-ically unsaturated monomers copolymerizable with said vinyl ether;

(G) mixtures of (F) with compatible phenolic compounds;

(H) mixtures of (F) with compatible aliphatic monohydric or polyhydric alcoholic compounds; and

(1) mixtures of (F) with compatible epoxidized materials containing at least one epoxide group per molecule.

15. A process as claimed in claim 14 wherein the pro- 32 portions of the ingredients of the expandable mixture are such that (D) the number of amido groups provided by the polyamide is less than 10% of the number of groups provided by the vinyl ether;

(E) the number of carbamate groups provided by the polycarbamate is less than of the number of H=CH groups provided by the vinyl ether;

(F) the number of ethy-lenic groups provided by the monoethylenically unsaturated compound is not more than three times the number of CH=CH groups provided by the vinyl ether;

(G) the combined number of ethylenic and hydroxyl groups provided by the monoethylenically unsaturated and phenolic compounds, respectively, ranges from less than 75% of the number of -CH=CH groups provided by the vinyl ether when the amount of phenolic compound exceeds that of monoethylenically unsaturated compound, to not more than three times the number of CH=CH groups provided by the vinyl ether when the amount of monoethylenically unsaturated compound exceeds that of phenolic compound;

(H) the combined number of ethylenic and hydroxyl groups provided by the monoethylenically unsaturated and alcoholic compounds, respectively, ranges from less than 75% of the number of CH=CH- groups provided by the vinyl ether when the amount of alcoholic compound exceeds that of monoe-thylenically unsaturated compound, to not more than three times the number of --CH=CH groups provided by the vinyl ether when the amount of monoethylenically unsaturated compound exceeds that of alcoholic compound; and

(I) the number of ethylenic groups provided by the monoethylenically unsaturated compound is not more than three times the combined number of and epoxide groups provided by the vinyl ether and epoxidized material, respectively.

References Cited by the Examiner UNITED STATES PATENTS 2,998,415 8/1961 Geiser 2609l.l 3,051,665 8/ 1962 Wismer 2602.5 3,128,258 4/ 1964 Doedens et al. 2602.5 3,232,892 2/1966 Fisher 260-25 MURRAY TILLMAN, Primary Examiner.

MORTON FOELAK, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3 ,311 ,574 March 28, 1967 William David Samuel Bowering et al It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 29, lines 41 to 45, the formula should appear as shown below instead of as in the patent;

Signed and sealed this 14th day of November 1967.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. EDWARD J. BRENNER Attesting Officer Commissioner of Patents 

1. A FOAMED CELLULAR POLYMERIC MATERIAL WHICH IS THE REACTION PRODUCT OF A FOAMABLE COMPOSITION COMPRISING: (A) AT LEAST ONE POLYMERIZABLE CYCLIC VINYL ETHER OF THE GENERIC FORMULA 